Administration of the MapR-DB is done primarily via the command line (maprcli) or with the MapR Control System (MCS). Regardless of whether the MapR-DB table is used for binary files or JSON documents, the same types of commands are used with slightly different parameter options. MapR-DB administration is associated with tables, columns and column families, and table regions.

The MapR Data Access Gateway is a service that acts as a proxy and gateway for translating requests between lightweight client applications and the MapR cluster. This section describes considerations when upgrading the service, how to modify configuration settings, and how to administer and manage the service.

These maprcli commands are used to create and manage Change Data Capture (CDC) changelogs. A changelog is used to establish a relationship between a MapR-DB source table (JSON or binary) and a MapR-ES stream topic and to manage the propagation process.

table region merge

Merges regions of a table together to reduce the number of regions that a table
occupies.

This command merges the region that you specify with the region that contains the
row keys that immediately follow the row keys of the specified region.

Note: Consider the table configuration when you decide to merge regions because it is
possible that MapR-DB might immediately split the regions after they are merged. If
autosplit is set to true, MapR-DB splits a region when the size of
the region exceeds 150% of the average value (regionsizemb). For
example, if the average value is 4096 MB, MapR-DB splits a region that is larger than
6144 MB.

Permissions Required

To run this command, your user ID must have the following permissions:

Note: The mapr user is not treated as a superuser.
MapR-DB does not allow the mapr user to run this command unless that user
is given the relevant permission or permissions with access-control expressions.

Parameters

The FID for the table region that you want to merge. The output of
maprclitable region list lists the FIDs for the table.

path

The path to the table whose regions are being merged.

For a path on the local cluster, start the path at the volume mount
point. For example, if you want to merge regions for table named
test under volume1 which has a mount point at
/volume1, specify the following path: /volume1/test

For a path on a remote, you must also specify the cluster name in the
path. For example, if you want to merge regions for table named
test under volume1 in the sanfrancisco cluster,
specify the following
path:/mapr/sanfrancisco/volume1/customer